About this replacement
ResMed VS Integra / VS Ultra — 24V Ni-MH Replacement Battery (B0402106)
This is a 24V, 2000mAh Ni-MH replacement battery for the ResMed VS Integra and VS Ultra non-invasive ventilators. It fits the internal battery bay on both units and provides backup power when AC supply is interrupted during treatment or patient transport. OEM part number B0402106 confirms fitment across both models.
- VS Integra and VS Ultra compatibility: Both ventilators share the same 24V battery bay geometry, connector pinout, and BMS communication protocol. One cell pack fits both without modification.
- Bench tested on actual hardware: We ran this pack through charge and discharge cycles on a VS Integra unit. The BMS recognised the cell chemistry, completed its verification handshake, and flagged no fault codes across repeated charge cycles.
- Post-swap startup sequence: After installing this battery, allow the VS Integra or VS Ultra to complete its full power-on self-test without interruption. The device runs a BMS verification pass at startup — cutting power during this sequence triggers a false battery fault that persists until the next clean reboot.
Why the VS Integra alarms low battery immediately after a confirmed full charge
The VS Integra's BMS stores a charge profile calibrated to the OEM cell's internal resistance baseline. A new replacement cell has a slightly different resistance signature until it completes its first full cycle. The BMS reads this mismatch as insufficient charge and triggers the low battery alarm even when the pack is at full capacity. Running one complete charge-to-discharge-to-full-recharge cycle allows the BMS to update its baseline and clear the alarm permanently.
VS Integra fails to power on after the replacement battery sat in storage
Ni-MH cells self-discharge during storage — typically losing 1–2% capacity per day without a maintenance charge. If the pack drops below the device's BMS recovery threshold (approximately 20V on a 24V Ni-MH pack), the ventilator will not complete its boot sequence. Connect the device to AC power and allow a full uninterrupted charge cycle before attempting to power on from battery alone. Confirm the charge indicator has reached 100% before disconnecting AC.